Process of determining features of a papermaking fabric based on sizes and locations of knuckles and pockets in the fabric

Patent metadata

Field	Value
Publication number	US-9988766-B2
Application number	US-201715469618-A
Country	US
Kind code	B2
Filing date	Mar 27, 2017
Priority date	Nov 14, 2013
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A process of determining features of a fabric. A representation of a portion of a surface of the fabric is formed showing locations and sizes of knuckles and pockets in the fabric surface. The representation is a print or a photograph of the fabric surface. An image is generated based on the representation. At least a portion of the image is displayed on a computer screen. The sizes and locations of the knuckles or pockets is determined. A unit cell is drawn for the portion of the fabric surface in the image. The unit cell is defined by guidelines that (i) pass through the centers of the knuckles and (ii) form shapes that surround areas of the image that correspond to where the pockets are formed between the knuckles. A fabric planar volumetric index is calculated based on properties of the unit cell formed by the guidelines.

First claim

We claim:

1. A process of determining features of a fabric, the process comprising:
forming a representation of a portion of a surface of the fabric, the representation showing locations and sizes of knuckles and pockets in the surface of the fabric, and the representation being one of (i) a print and (ii) a photograph of the surface of the fabric;
generating an image of the portion of the surface of the fabric based on the representation that is formed;
displaying at least a portion of the image on a screen associated with a computer having a processor;
determining the sizes and locations of the knuckles in the display of the at least a portion of the image;
determining the sizes and locations of the pockets in the display of the at least a portion of the image;
drawing a unit cell for the portion of the surface of the fabric in the displayed image, wherein the unit cell is defined by guidelines that (i) pass through the centers of the knuckles and (ii) form shapes that surround areas of the image that correspond to where the pockets are formed between the knuckles; and
calculating a planar volumetric index of the fabric based on properties of the unit cell defined by the guidelines,
wherein the guidelines are drawn using an image analysis program stored in a non-transitory computer-readable medium.

2. The process according to claim 1 , wherein the fabric is a papermaking fabric.

3. The process according to claim 1 , wherein the planar volumetric index includes two variables: the contact area ratio (CAR) and the effective pocket volume (EPV).

4. The process according to claim 3 , wherein the contact area ratio is defined as the ratio of the contact area formed by knuckles in the structuring fabric to an open area in the web contacting side of the structuring fabric.

5. The process according to claim 4 , wherein the effective pocket volume is defined as an average volume of pockets in the structuring fabric into which cellulosic fibers of the web may migrate during a papermaking operation.

6. The process according to claim 5 , wherein the planar volumetric index is about 27 to about 31.5.

7. A process of determining features of a fabric, the process comprising:
forming a representation of a portion of a surface of the fabric, the representation showing locations and sizes of knuckles and pockets in the surface of the fabric, and the representation being one of (i) a print and (ii) a photograph of the surface of the fabric;
generating an image of the portion of the surface of the fabric based on the representation that is formed;
displaying at least a portion of the image on a screen associated with a computer having a processor;
determining the sizes and locations of the knuckles in the display of the at least a portion of the image;
determining the sizes and locations of the pockets in the display of the at least a portion of the image;
drawing a unit cell for the portion of the surface of the fabric in the displayed image, wherein the unit cell is defined by guidelines that (i) pass through the centers of the knuckles and (ii) form shapes that surround areas of the image that correspond to where the pockets are formed between the knuckles; and
calculating an adjusted planar volumetric index of the fabric based on properties of the unit cell defined by the guidelines,
wherein the guidelines are drawn using an image analysis program stored in a non-transitory computer-readable medium.

8. The process according to claim 7 , wherein the shapes are non-rectangular, parallelograms.

9. The process according to claim 8 , wherein the adjusted planar volumetric index includes two variables: the contact area ratio (CAR) and the effective pocket volume (EPV).

10. The process according to claim 9 , wherein the contact area ratio is defined as the ratio of the contact area formed by knuckles in the structuring fabric to an open area in the web contacting side of the structuring fabric.

11. The process according to claim 10 , wherein the effective pocket volume is defined as an average volume of pockets in the structuring fabric into which cellulosic fibers of the web may migrate during a papermaking operation.

12. The process according to claim 11 , wherein the adjusted planar volumetric index is defined as the contact area ratio (CAR) multiplied by the effective pocket volume (EPV) multiplied by one hundred.

13. The process according to claim 12 , wherein the contact area ratio (CAR) and the effective pocket volume (EPV) are calculated using a non-rectangular, parallelogram unit cell area calculation technique.

14. The process according to claim 7 , wherein the fabric is a papermaking fabric.

Assignees

• Gpcp Ip Holdings Llc

Inventors

• Chou Hung Liang
• Sze Daniel H
• Fan Xiaolin

Classifications

• D21F11/006

  Making patterned paper · CPC title

• D21H27/007

  relating to absorbency, e.g. amount or rate of water absorption, optionally in combination with other parameters relating to physical or mechanical properties · CPC title

• D21H27/005

  relating to physical or mechanical properties, e.g. tensile strength, stretch, softness · CPC title

• D21H27/38

  at least one of the sheets having a fibrous composition differing from that of other sheets · CPC title

• D21H27/30 Primary

  Multi-ply (for surface covering D21H27/18; making on paper-making machines D21F9/00, D21F11/00) · CPC title